Why Do We Need Fiber?

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Why Do We Need Fiber?
(The need for more speed)

A Study on Video Over IP and
the Effects on PON Architectures
(The need for more speed)
Why Do We Need Fiber?
A Study on Video Over IP and the Effects on
PON Architectures
It can be argued that eventually, everything will be IP; Voice, Data, Video and even wireless,
completing the “IP Quadruple Play.” When and how soon is anyone’s guess, but the impact
on existing and future networks is going to push the need for more speed (bandwidth).
IP to and in the home will usher in a new range of entertainment and services:
− Voice over IP (VoIP)
− IPTV (SDV – Switched Digital Video)
− Music Distribution
− Personal Video Recorder (PVR)
− Video On Demand (VoD)
− High Definition TV (HDTV)
− Interactive Television
− IP Enabled Appliances (Smart Appliances)
− Security, Environment (Smart Home)
Of these services, video is the most demanding in terms of bandwidth and more
significantly, how we view the quality of the entertainment (QoE). CED magazine has
written several articles highlighting video bandwidth needs such as; “The Big Squeeze,”
by Craig Kuhl, Contributing Editor, April 1, 2006 and “Bracing for the Impact,” by Jeff
Baumgartner, Editor in Chief, CED magazine and xOD Capsule, July 2006.
Page 3
A Study on Video Over IP and the Effects on PON Architectures
IPTV

So, what is IPTV? For many, the acronym conjures up
visions of hundreds of “on-demand” entertainment
channels delivered anytime, anywhere. IPTV (Internet
Protocol Television) describes a system where a digital
television service is delivered using the Internet Protocol
over a network infrastructure, which may include delivery
by a single broadband connection. For residential users,
this type of service is often provided in conjunction with
Video on Demand (VoD) and may be part of combined
Internet Services such as Web access and Voice over IP
(VoIP), where it may then be called Triple Play. Anything
over IP is typically supplied by a broadband operator
using a single infrastructure. It promises total control by
the user to customize their multimedia experience for
true interactive uni-casting entertainment and services.
For many operators, IPTV holds the allure of tapping
into new revenue sources with the delivery of advanced
multimedia services over broadband networks.
IPTV is being enabled with the transition of moving from
an analog format to an all-digital format. Advances in
video compression techniques are making it easier to
deliver both standard and high definition audio and
video. The growth in bandwidth, coupled with digital
video and better compression techniques, broadband can
be delivered to an ever-increasing subscriber base over
anything Digital Subscriber Line (xDSL) or passive optical
networks (PON) networks. With increased consumer
demand fueling the fire, competition is on the rise.
As competition grows fiercer, what’s the best way to
deploy IPTV? The answer, there is no single answer.

Today, the basic delivery mechanisms include Digital
Subscriber Line (DSL), Passive Optical Networks (PON) as
in fiber-to-the-home (FTTH), traditional CATV over Hybrid
Fiber Coax (HFC), or some combination. Each has its
advantages and challenges.
This study investigates the key elements of IPTV over PON
deployments by addressing the following four aspects:
Technology: What are the enabling technologies and
their availability timeline?
Capacity: What are the differences between various
PON implementations? Can they meet the service
requirement?
Cost: What are the cost differences among various PON
options?
Business: How are the services priced? What is the
impact on revenues? Is cost a significant portion of the
revenues?
Technology
Starting with a brief bit of history about IPTV and some
of the standards that dictate how we deliver video
combined with audio over an all IP format. Digital
Broadcast Satellite (DBS) (i.e. satellite TV) is not discussed
in great detail.
Direct Broadcast Satellite (DBS) is a term used to
refer to satellite television broadcasts intended for home
reception, also referred to as direct-to-home signals. It
covers both analog and digital television, radio reception,
and is often extended to other services provided by
digital television systems including limited video-on-
demand and interactive features. A "DBS service" usually

refers to either a commercial service, or a group of free
channels available from one orbital position satellite
targeting one country. DirecTV and EchoStar are a couple
of examples.
Typical xDSL Development and the Moving
Picture Experts Group (MPEG)
With current video compression technologies, neither
Symmetric High Bit-Rate Digital Subscriber Loop (SHDSL)
nor Asymmetrical DSL (ADSL) can provide the bandwidth
required for IPTV. ADSL2+ at 26 Mbps and Very high-
speed DSL (VDSL) at 50 Mbps offer more bandwidth,
but the tradeoff is in the distance. Subscribers need to
be close to the Central Office (CO) or remote terminal
as the speed over any xDSL network decreases over
longer distances. Many operators find IPTV deployment
over xDSL more attractive given existing investments
in the copper plant and the need to deliver services
quickly. However, one of the key problems in xDSL is
the delivery of standard definition and high-definition
TV over MPEG2. With MPEG2, HDTV currently requires
approximately 20 Mbps per channel compared to 2.5
– 3.5 Mbps for standard-definition TV. (See the Table 1
below for broadcast bandwidths of MPEG2.)
MPEG4 is the next step in compression techniques and
is a standard similar to MPEG2 that primarily compresses
the audio and video (AV) digital data. Introduced in late
1998, MPEG4 is the designation for a group of audio
and video coding standards and related technology
agreed upon by the ISO/IEC Moving Picture Experts
Group (MPEG). The services used over the MPEG4

Table 1. Bandwidth Requirements Under MPEG2 Standards
<0.384 Mbps Video conference (MPEG4)
<1.5 Mbps Video in a window (MPEG1)
1-2 Mbps VHS quality full screen (MPEG2)
2-3 Mbps Broadcast NTSC (MPEG-2)
4-6 Mbps Broadcast PAL (MPEG-2)
8-10 MBPS Professional PAL (MPEG-2)
12-20 Mbps Broadcast HDTV (MPEG-2)
27.5-40 MBPS DVB satellite multiplex (MPEG-2 Transport)
32-40 Mbps Professional HDTV (MPEG-2)
34-50 Mbps Contribution TV (MPEG-2-1)
140 Mbps Contribution HDTV (MPEG-2-1)
168 Mbps Raw NTSC (uncompressed)
216 Mbps Raw PAL (uncompressed)
270 Mbps Raw contributin PAL (uncompressed)
1-1.5 Gbps Raw HDTV (uncompressed)
A Study on Video Over IP and the Effects on PON Architectures
Page 4
standards include video on the web (Streaming Media),
CD distribution, conversation (videophone), and
broadcast television. MPEG4 uses enhanced features of
MPEG1 and MPEG2 and other related standards, while
adding new features such as (extended) Virtural Reality
Modeling Language (VRML) that supports 3D rendering.
Other MPEG4 features include object-oriented composite
files (including audio, video and VRML objects), support
for externally-specified Digital Rights Management, and
various types of interactivity such as video on demand
(VOD). Most of the features included in MPEG4 are left
to individual developers to decide whether to implement

them, and this has caused some of the delay in making
MPEG4 commercially available. This means that there
are probably no complete implementations of the
entire MPEG4 set of standards. In order to combat this
issue, the standards include the concept of "profiles"
and "levels" allowing a specific set of capabilities to be
defined and used in a manner appropriate for a subset of
applications and networks.
The New Industry Standard
Already ratified as part of the MPEG-4 standard
— MPEG-4 Part 10 — and the ITU-T’s latest video-
conferencing standard, H.264 are now mandatory for the
HD-DVD and Blu-Ray specifications (the two formats for
high-definition DVDs) and ratified in the latest versions
of the DVB (Digital Video Broadcasters) and 3GPP (3rd
Generation Partnership Project) standards. Numerous
broadcast, cable, videoconferencing and consumer
electronics companies consider H.264 as the video
codec of choice for their new products and services. This
adoption by a wide variety of open standards means that
any company in the world can create devices — mobile
phones, set-top boxes, DVD players and more — that will
offer the newly formatted HDTV specifications. Currently,
these devices are not yet ready for prime time and when
they will be released is uncertain.
The one area that has been settled with MPEG4 Part 10
is the need to compress the video and audio even more
making it easier for various network architectures and
their delivery mechanisms. (See the Table 2 below for
broadcast bandwidths of MPEG4 Part 10.) How many

video feeds that can be offered to the consumer is of
particular importance in delivering IPTV.
Requirements for Multiple Video Feeds
After investigating the drivers for more video feeds per
subscriber, the findings show that multiple video feeds
are no longer independently driven by the number of TV
sets per household. Today, 98.2% of all U.S. households
have a television set, and 74.3% of those households,
have two or more sets. (Source: Nielsen Media Research)
Another recent statistic shows that four of every five TV
sets sold today are HDTV Sets. (Source: Harvard Research)
Table 3 below shows the HDTV Subscriber Growth in
millions of households. (Source: The Yankee Group,
Company reports, public statements, NAB, NCTA.)
An additional driver in the push towards digital video
broadcasting is that the Federal Communications
Commission (FCC) TITLE VII—DIGITAL TELEVISION is
mandating the termination of analog broadcast by
February 2009. Studying the currents trends of the local
broadcast stations, these stations are not just going
digital, but they are using “high definition” digital. This
alone is going to place a burden on the current delivery
systems and the future delivery systems.

Use Scenario
Resolution and
Frame Rate
Example
Data Rates
Mobile Content 176x144, 10-15 fps 50-60 Kbps

Internet/Standard
Definition
640x480, 24 fps 1-2 Mbps
High Definition 1280x720, 24 fps 5-6 Mbps
Full High Definition 1920x1080, 24 fps 7-8 Mbps
Table 2. Bandwidth Requirements
Under MPEG4 Part 10 Standards
3.4
8.3
16.2
27.5
57.5
59.3
7.1
12.1
19.3
29.9
43.9
42.2
0
15
30
45
60
2003 2004 2005 2006 2007 2008
Number HDTV Sets
Number Homes Receivin g HDTV Services
millions
Table 3. HDTV Subscriber Growth
Title VII Mandates the addition of labels on analog TVs,

apprising consumers of the termination of analog broadcast
in February 2009. Calls for additional consumer education
on the upcoming digital transition, including the formation
of a DTV Working Group on Consumer Education, Outreach,
and Consumer Education. Allows "down-conversion" of
digital signals to analog by cable operators seeking to serve
their analog customers.Reinstates the FCC's 2000 rules
requiring video description of digital programming, designed
to serve sight-impaired audiences.”
A Study on Video Over IP and the Effects on PON Architectures
Page 5
Capacities
PON Capacities
The objective when examining the PON capacity is to
determine whether a particular PON implementation can
meet a given service bandwidth requirement. This is not
only important in the southbound PON Port capacities,
but more importantly in the northbound interfaces where
multi-casting techniques will be initiated.
PON capacity must meet maximum usage without video
blocking for any given take rate. The PON architecture
must be engineered to handle regular usage by the
given take rates and have the ability to ensure video
service during peak times in the network. Individual PON
capacity determines the maximum number of video feeds
per subscriber, when the video compression techniques
are initially set at the MPEG2 Standards. Again,
multicasting is going to be critical in the ability of any
PON architecture to be able to provide adequate video
services to the subscriber.

Video Compression
MPEG-2
Total SD Channels
Total HD Channels
BPON 622Mbps
1:32
BPON
1.25Gbps 1:32
GEPON
1.25Gbps 1:32
GPON 2.5Gbps
1:32/1:64
Service Offer
MPEG-4 Part 10
Systems
commercially
available
Systems
commercially
available
Components
commercially
available
H.264
Standard
Ratified
350325
352515
Systems
commercially

available
Standard
Amendment
Ratified
Systems
commercially
available
Components
commercially
available
802.3ah
Standard
Ratified
Systems
commercially
available
Components
commercially
available
2004 2005 2006 20072003
20022001
First Major PON
Deployments
2008
PON
2004 2005 2006 2007 200320022001 2008
300
G.984.3
Standard
Ratified

Systems
commercially
available
Components
commercially
available
G.983
Content
Provider
Adoption
Table 4. Timeline for PON Bandwidths, Video Compression, and Service Offering
Exhibit 1. PON Capacities in the Northbound and
Southbound Interfaces
OLT Trunk Capacity
(North Bound Interface)
OLT
CO
N subs
PON Capacity
1:N Split
N subs
1:N Split
N subs
1:N Split
PON Bandwidths and MPEG Comparisons
This section will focus is on the support of IPTV by various PON architectures, including Broadband PON (BPON), with data
rates of 622/1.2 Mbps Down Stream (DS), Gigabit Ethernet PON (GEPON), with data rates of 1.2 Mbps DS, and Gigabit
PON (GPON), with data rates of 2.4 Mbps DS.
Based upon the timeline in Table 4, deployment strategies should take advantage of mature technologies such as MPEG-
2 and BPON while ensuring an upgrade path to the new technologies of GEPON and GPON as well as MPEG4.